USE OF THE ENDOTRACHEAL-TUBE AS A PHARYNGEAL AIRWAY

An animal study was conducted to determine whether an endotracheal tub e placed above the vocal cords in the pharynx can be used for ventilat ion. Four dogs undergoing general anesthesia were ventilated through a n endotracheal tube placed in the oropharynx with the remain der of th e airway occluded, Ventilation was performed for 3 of every 5 minutes during a total period of 25 minutes, Arterial PCO2 was compared in seq uential samples alternating apnea and pharyngeal ventilation, Ventilat ion via the pharyngeal tube significantly reduced the arterial PCO2 fr om 48.8 mm Hg (SD 16)during apnea to 30.1 mm Hg (SD 10.9), Repeated me asures ANOVA F = 8.2, P < .001. All PCO2 levels during ventilation wer e in or below the normal range of 34 to 46, Provided that the mouth an d nose can be sealed, an endotracheal tube placed in the pharynx above the cords allows for adequate ventilation. (C) 1996 by W.B. Saunders Company